package com.usian.admin.gateway.filter;

import com.usian.admin.gateway.utils.AppJwtUtil;
import io.jsonwebtoken.Claims;
import org.apache.commons.lang3.StringUtils;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.http.HttpHeaders;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

@Component
public class AuthorizeFilter implements GlobalFilter, Ordered {
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        //1.获取请求对象和响应对象
        ServerHttpRequest request = exchange.getRequest();
        ServerHttpResponse response = exchange.getResponse();
        //2.判断当前的请求是否为登录，如果是，直接放行
        if(request.getURI().getPath().contains("/login/in")){
            //放行
            return chain.filter(exchange);
        }
        //3.获取当前用户的请求头jwt信息
        HttpHeaders headers = request.getHeaders();
        String jwtToken = headers.getFirst("token");

        //4.判断当前令牌是否存在
        if(StringUtils.isBlank(jwtToken)) {
            //如果不存在，向客户端返回错误提示信息
            String json = "{\"errorMsg\":\"don't have token\"}";
            return response.writeWith(Flux.just(response.bufferFactory().wrap(json.getBytes())));
        }

        try {
            //5.如果令牌存在，解析jwt令牌，判断该令牌是否合法，如果不合法，则向客户端返回错误信息
            Claims claims = AppJwtUtil.getClaimsBody(jwtToken);
            int result = AppJwtUtil.verifyToken(claims);
            if(result == 0 || result == -1){
                //5.1 合法，则向header中重新设置userId
                Integer id = (Integer) claims.get("id");
                ServerHttpRequest newRequest = request.mutate().headers(httpHeaders ->
                        httpHeaders.add("userId", id + "")).build();
                exchange.mutate().request(newRequest).build();
            }else {
                //token续签
            }
        }catch (Exception e){
            e.printStackTrace();
           String json = "{\"errorMsg\":\"token is invalid\"}";
           return response.writeWith(Flux.just(response.bufferFactory().wrap(json.getBytes())));

        }
        //6.放行
        return chain.filter(exchange);
    }

    //级别
    @Override
    public int getOrder() {
        return 0;
    }
}
